Centre for Biodiversity and Environment Research, University College London, London, UKGroningen Institute for Evolutionary Life Sciences, University of Groningen, PO Box 11103, Groningen 9700 CC, The Netherlands

Seddon et al. (2016) highlight the urgent need to better integrate multiple different values of biodiversity into decision-making supporting sustainable development. They make a good start on this in focussing explicitly on those biodiversity values associated with “ecological processes”:
“biodiversity supports human well-being either directly through enhanced ecosystem functions and services … or indirectly by increasing the resilience of such functions in the face of environmental change.”
But ecological processes do not have to be the only processes regarded as important. One complementary perspective explores biodiversity values associated with evolutionary processes (e.g. Faith et al 2010). This perspective expands beyond those within-ecosystem functions and services to also highlight global biodiversity “option values”. For example, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) “Conceptual Framework” has recognised “the option values of biodiversity as a reservoir of yet-to-be discovered uses from known and still unknown species and biological processes, and as a constant source, through evolutionary processes, of novel biological solutions to the challenges of a changing environment.” (Diaz et al 2015).
Biodiversity option values are not discussed by Seddon et al, but can fit into an expanded version of their “economic valuation approaches to biodiversity conservation”. The “Biodiversity Synthesis” of the Millenniu...

Seddon et al. (2016) highlight the urgent need to better integrate multiple different values of biodiversity into decision-making supporting sustainable development. They make a good start on this in focussing explicitly on those biodiversity values associated with “ecological processes”:
“biodiversity supports human well-being either directly through enhanced ecosystem functions and services … or indirectly by increasing the resilience of such functions in the face of environmental change.”
But ecological processes do not have to be the only processes regarded as important. One complementary perspective explores biodiversity values associated with evolutionary processes (e.g. Faith et al 2010). This perspective expands beyond those within-ecosystem functions and services to also highlight global biodiversity “option values”. For example, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) “Conceptual Framework” has recognised “the option values of biodiversity as a reservoir of yet-to-be discovered uses from known and still unknown species and biological processes, and as a constant source, through evolutionary processes, of novel biological solutions to the challenges of a changing environment.” (Diaz et al 2015).
Biodiversity option values are not discussed by Seddon et al, but can fit into an expanded version of their “economic valuation approaches to biodiversity conservation”. The “Biodiversity Synthesis” of the Millennium Ecosystem Assessment (MEA 2005a) reviewed such biodiversity valuation approaches and concluded that:
“There is substantial scope for greater protection of biodiversity through actions justified on their economic merits for material or other benefits to human well-being. Conservation of biodiversity is essential as a source of particular biological resources, to maintain different ecosystem services, to maintain the resilience of ecosystems, and to provide options for the future” (the MEA also referred to “unexplored options for the future” as “option values”).
Seddon et al focus on ecosystem functions/services and resilience (see quote above). That MEA list of biodiversity benefits/values explicitly includes those, plus biodiversity option values as another important core benefit. Explicitly including all of these benefits/values promotes a more integrative, inclusive, way to approach sustainability that balances society’s valuation of the benefits from various land uses (e.g. agriculture), from within-ecosystem biodiversity, and from global biodiversity. The global biodiversity benefits corresponding to option values typically will imply less interest in the total biodiversity of any given place, and more interest in its degree of complementarity – the marginal gain it offers in overall global biodiversity conservation. Thus, while Seddon et al promote ecological processes and “biodiverse ecosystems”, regional/global sustainability also depends on complementarity of areas and (sometimes) low-biodiversity land uses.
Seddon et al suggest that key ecological processes be referred to as “biodiversity services”, which are to be seen as “the foundation to all other functions and services provided by the ecosystem”. Their examples of these biodiversity services of ecosystems included community assembly, interaction networks, nutrient transfer and biogeochemical cycling. I think that “biodiversity services”, if it is to be an informative general term, should capture more than ecological processes. In fact, I previously have used that term “biodiversity services” in this way, referring to the contributions that places can make to overall regional or global biodiversity option values (Faith et al 2003).
Full appreciation of the idea that “biodiversity services” include more than ecological processes may require re-visiting our definitions of “biodiversity”. Seddon et al. defined “biodiversity” as “the diversity of genes, traits, species, habitats and landscapes”. That word “diversity” has a range of ecological interpretations. A co-author of the Seddon et al review, Georgina Mace, previously has promoted “diversity” as the basis for a broad ecological interpretation of “biodiversity” (“the definition embraces many alternative diversity measures”; Mace et al 2012). This included, for example, indices reflecting relative abundance of species. Such a broad ecological interpretation accords with Seddon et al’s call for more work on finding the “mechanistic links between species and the functioning and resilience of ecosystems” in order to “protect those elements of diversity crucial for ecosystem integrity.”
No doubt lots of ecology indices will have a bearing on “ecological integrity”. In contrast, when considering biodiversity option values, “biodiversity” typically is associated with the core idea of living variation, interpretable as counting-up numbers of different units (e.g. species). Thus, in this case, there is no required link to abundance-weighted and other ecological diversity indices (for discussion, see Faith 2017).
The priorities we set for decision-making will vary depending on what we focus on in defining “biodiversity”. “Biodiversity” management within ecosystems focussed on “diversity” and “ecosystem integrity” probably cannot be expected to also guarantee global conservation of biodiversity. Indeed, emphasis on biodiversity’s contributions to people from ecosystem functions/services and resilience may mean less attention to global biodiversity option values. Decision-making that truly integrates multiple biodiversity values may require first sorting out our multiple definitions of biodiversity.
References
Dı´az S et al. 2015 The IPBES conceptual framework—connecting nature and people. Curr. Opin. Environ. Sust. 14, 1–16. (doi:10.1016/j.cosust.2014.11.002)
Faith DP et al. 2010 Evosystem Services: an evolutionary perspective on the links between biodiversity and human-well-being. Curr. Opin. Environ. Sust. 2, 66–74.
Faith DP 2017 A general model for biodiversity and its value. in The Routledge Handbook of Philosophy of Biodiversity (Eds. J Garson, A Plutynski, S Sarkar)
Faith DP et al. 2003 Complementarity, biodiversity viability analysis, and policy-based algorithms for conservation. Environmental Science & Policy 6, 311–328.
Mace GM et al. 2012 Biodiversity and ecosystem services: a multilayered relationship. Trends Ecol. Evol. 27, 19–26.
Millennium Ecosystem Assessment 2005a Ecosystems and Human well-being - Responses Assessment, Chapter: Biodiversity, Island Press, Eds: K Chopra, R Leemans, P Kumar, H Simons, pp.122-172.
Millennium Ecosystem Assessment 2005b Ecosystems and Human Well-being: Biodiversity Synthesis. World Resources Institute, Washington, DC.
Seddon N et al. 2016 Biodiversity in the Anthropocene: prospects and policy Proc. R. Soc. B 283, 20162094.